Alexis Sanchez was too 'skinny' to play a central-attacking role when he first joined Udinese

Manchester United star Alexis Sanchez decided to run eight kilometres home after locking his keys in his car following training at former club Udinese.

That’s the story from an Italian journalist who tracked Sanchez’s progress during his time with Serie A club.

Sanchez’s career began in his native South America before he joined Udinese aged 20.

He shone in three years in Italy and earned a move to Spanish giants Barcelona, where he won six trophies, before moving to England with Arsenal in 2014. He added two FA Cups to his haul of silverware with the Gunners before becoming the Premier League’s highest-paid player when he joined Manchester United in January.

Sanchez has demonstrated his power, pace and clinical eye for a goal since arriving on English soil, but he wasn’t always the athlete he is now.

The Chilean ace made conscious effort to bulk up and build his physique during his time in Italy, and sports writer Pietro Oleotto has revealed the lengths Sanchez went to to improve his fitness during the early stages of his career.

“In his first season, he [Alexis] was skinny and stayed on the right wing a lot,” Oleotto told Inside United magazine.

“The physicality in the penalty area was too much for him. But the team needed him more central, closer to the goal, to make the most of his dribbling.

“So he began improving his body and they built him an ad-hoc gym. He worked out for two hours a day after training. I remember seeing him halfway through pre-season training camp and being shocked by how much muscle he had put on.

“Once, after training, Alexis drove into Udine to do some shopping. But he accidentally locked his keys and mobile phone in his car.

“I’m not sure what most people would have done, but he just ran home. He jogged the 8km from the heart of the city to his house in the hills. Bemused locals saw him in his club tracksuit running and called us at the paper. It was typical of Alexis to turn the situation into an improvised cross-country run.”